1. Field of the Invention
The present invention relates to a medical device and, more particularly, to a medical device that can be properly used for medical treatment in which negative pressure is locally applied in the body.
2. Description of Related Art
There are various types of inflammation which occur at bursiform cavities in a body. For example, in an anterior resection of the rectum, when a complication is caused, an anastomotic leak is caused and may be developed to abscess formation. The best way to treat such an abscess occurring in the body is not known, and surgical procedures such as drainage of fluid, anastomosis excision, fistula formation, etc. and conservative procedures such as administration of broad-spectrum antibiotics, restriction of food ingestion based on parenteral nutrition, etc. are conducted.
The inflammation of the bursiform cavities in the body may include, for instance, appendicitis. Appendicitis is often treated by excising the vermiform appendix. On the other hand, when appendicitis is suspected, there are cases in which the appendicitis can be treated without excising the vermiform appendix, and cases in which there is no actual appendicitis.
As one of the aforementioned methods of treating the abscess or the inflammation, a wound treatment based on negative pressure (negative pressure therapy) is known. The negative pressure therapy is disclosed in, for instance, Published Japanese Translation No. 2006-505316 of the PCT International Publication. According to a specific example of this therapy, a foam is positioned and disposed in a bursiform cavity (including an abscess) in the body of a patient using an introducer as a collecting means for collecting contents of the bursiform cavity. The foam is, for instance, an open-cell polyurethane ether foam. This foam is connected to a vacuum device via a flexible thin tube. The vacuum device is equipped with a collecting unit that collects an outflow such as a liquid forcibly discharged from the bursiform cavity and a negative-pressure source that maintains the cavity under negative pressure.
When the disposition of the foam is completed, the introducer is removed. Next, the negative pressure is applied to the foam. Since this negative pressure is uniformly applied to a wall of the cavity by the foam, the bursiform cavity is contracted. As a result, the outflow such as liquid or necrotic tissue which is present in the cavity is forcibly discharged from the cavity. This discharge is collected in the collecting unit via a tube. Thereby, the inflammation in the cavity is effectively treated. After the treatment is completed, the foam is removed.
In the case of the negative pressure therapy, it is necessary to seal the bursiform cavity. In the case of the technique set forth in Published Japanese Translation No. 2006-505316 of the PCT International Publication, a sealing is achieved by a shape of the cavity treated by the foam as a pressure distributor, a structure (e.g., an anus of a patient) of a passage of the body into which the introducer is pressed, or a certain adhesive drape used for vacuum adjunct treatment of the surface of the body.